Method and means for producing a wave consisting of a carrier amplitude modulated by a signal, with the carrier suppressed, receiving such a wave and demodulating it without reinsertion of the carrier, to produce the signal.
In the prior art a wave consisting of a carrier, double sideband amplitude modulated by a signal, with the carrier suppressed, known as a DSBSC wave, is used with a receiver in which the carrier is reinserted before demodulation to recover the signal.
In this invention the DSBSC wave is produced as in the prior art, and the receiver demodulates the wave by full-wave rectification, followed by reversal of alternate portions of the demodulated wave, spaced between instants at which the signal has successive zero crossings.
The system and the receiver of this invention have utility, as they allow transmission of signals without the complications of synchronization and reinsertion of the carrier at the receiver.